The symbol derives from a capital "L", representing libra, the basic unit of weight in the Roman Empire, which in turn is derived from the Latin name of the same spelling for scales or a balance. The pound became an English unit of weight and was so named because it originally had the value of one tower pound (~350 grams) of fine (pure) silver.

The pound sign is placed before the number (e.g. "£12,000") and separated from the following digits by no space or only a thin space.

The symbol ₤ was called the lira sign in Italy, before the adoption of the euro. It was used as an alternative to the more usual L to show prices in lire. It was also used unofficially as the symbol of the Maltese lira instead of the official Lm.

In American English, the term "pound sign" usually refers to the symbol # (see number sign), and the corresponding telephone key is called the "pound key".[1] The symbols £ and # are both referred to as the pound sign in Canadian English (# is also referred to as the "number sign" and "norts-and-crosses board").[2]

In the original old Caslon metal fonts, the pound sign was identical to the italic capital "J" rotated 180 degrees.[citation needed]

Unicode notes that the "lira sign" is not widely used, and the preferred sign for lira is the pound sign.[contradictory] Some fonts render the pound sign with a double bar (for example on a previous version of the British five pound note[5]); this is simply a different glyph, and the underlying character (and therefore Unicode codepoint) is still a pound sign, and not a lira sign.

Entry methods

Historical

Prior to the introduction of the IBM PC, there was no unique accepted standard for entering, displaying, printing, or storing the £ sign in the UK computer industry. On personal computers prior to the PC the "#" key was often used; sometimes it was displayed on screen as "#", but many printers could be set up to print "£" where "#" was sent to the printer by an application program. Keying in, storing, displaying, and printing the sign often required special set-up. Although the "#" sign is commonly called the "hash symbol", it is also referred to as the "pound sign" in North America (though in reference to the unit of weight, not the unit of currency). It is also known as the number symbol or key.

The Commodore 64 computer included a dedicated key for the pound sign (to the right of the number row).

The BBC Micro used a variant of ASCII that replaced the backtick ("`", character 96, hex 60) with the pound sign (ISO/IEC 8859 had not yet been standardised, and it was advantageous to have commonly used characters available in the lower, 7-bit ASCII table), denoted as CHR$96 or (hex) CHR$&60. Since the BBC Micro used a Teletext mode as standard, this means that the pound sign is in the 7-bit ASCII variant used on Teletext systems such as Ceefax, ORACLE and Teletext Ltd as well.

On Latin-alphabet typewriters lacking a "£" symbol type element, a reasonable approximation can be made by typing an "f" over an "L".

Compose key

Printing

In the 1980s, the two main standards for the print codes for a pound sign were ASCII 186 for the HP Laserjet and ASCII 156 for most other printers including the IBM Quietwriter and Epson dot matrix printers. In order to print a pound sign, each word processor needed to be set up individually to print the sign for a particular printer. For many word processors a terminate and stay resident program (TSR) was needed to convert the code generated by the package into the right code for the printer. Packages such as WordPerfect had utilities to set up this conversion without needing a TSR.